1. Field
This application relates generally to the use of aerodynamic wing load distribution control for increasing flight performance of an aircraft.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
It is known to improve structural fatigue life at the cost of a decrease in flight performance of a C-5A aircraft, e.g. an increase in drag, via aerodynamic wing load distribution control provided by uprigging the aircraft's ailerons. The aileron uprig, which decreases swept wing bending moments and torsional loads on the wings of the C-5A, involves increasing, by an equal amount, the degree of trailing edge-up deflection or “uprig” of both left and right wing ailerons. To provide the uprig an adjustment is made to respective neutral positions of the left and right wing ailerons by shortening respective left and right aileron feedback rods. The adjustment is made in such a way that an equal amount of trailing edge-up deflection is maintained by both the left and the right ailerons while still allowing operators to command differential deflections through roll control inputs to the ailerons via an operator interface. Also, studies have indicated that a “static” load reduction objective could be attained with a two position system having 5 degrees of uprig above 20,000 feet, 10 degrees of uprig below 20,000 feet, and the 5 degree setting in takeoff and landing configuration.
Another example of a known load distribution control system is an active load distribution Control System (ALDCS) apparatus that moves aileron and elevator control surfaces of a swept wing aircraft in response to command signals and input from sensors that detect gust and maneuver loads applied to the wings of the aircraft. A controller dynamically compensates for swept wing torsional loads by moving the ailerons and elevators in response to signals that are received from the sensors and that correspond to gust and maneuver loads perceived by the sensors.